Syringe.



C. P. DEWITT.

' SYRINGE.

APPLICATION FILED 21m, 1913.

1,084,257, Patented Jan. 13, 1914.

6 m fan/wow 05 m TT IFTCE.

CARL FRIEDRICH IDE'WITT, OF BERLIN, GERMANY.

SYRINGE.

Application filed February 4:, 1913.

To all whom it may concern:

Be it known that I, CARL FRIEDRICH Dnwrrr, of 24: Georgenkirchstrasse,Berlin, Germany, a subject of the German Emperor, have invented certainnew and useful Improvements in or Relating to Syringes, of which thefollowing is a specification.

In syringes for medical use with exchangeable nozzle the latter isconnected to the barrel in various manners. The usual man nor is to packthe glass barrel at its end in its guard shell which as a rule has aconical seat to receive the shank of the nozzle. This method isunsuitable, because it will be necessary to provide a packing betweenbarrel and guard. In order to avoid this it has been tried to unite thenozzle and barrel by fusing the shank of the nozzle into acorrespondingly thicker bottom of the barrel. But in this case thenozzle is rigidly secured to the barrel and cannot be removed there fromand be exchanged as it may become necessary. If the opening in thebottom of the barrel were to be drawn out so far, that the nozzle mightbe inserted into the tube thus produced on the barrel, the trouble isencountered, that this tube will easily break oil, as a certain amountof force will be necessary to fit the nozzle tightly, when it has aground conical shank.

The present invention relates to a syringe for medical purposes in whichthe advan tages of the usual method of uniting the nozzle and barrel arecombined and the disadvantages avoided, by a solid bottom with groundconical seat for the nozzle being employed. The bottom, the thickness ofwhich corresponds approximately to the length of the shank of the nozzleaffords a sufficient resistance for the nozzle to be tightly fitted intoit, so that the barrel will not break here. On the other hand it is easyto detach the nozzle again and clean the several parts of the syringewithout any packing being necessary.

In case it is necessary to secure the nozzle in the barrel against itsbeing unintentionally forced out while the syringe is being used, thismay be obtained according to a further feature of the present inventionby a bayonet lock being provided between the nozzle and the barrelguard, for instance by the nozzle or its shank having a pin projectingon one side and the barrel guard being provided with a correspondingslot- Specification of Letters Patent.

Patented Jan. 13, 1914.

Serial No. 746,224.

in which the said pin engages and locks. Of course the arrangement mayalso be made the other way, so that the pin is attached to the barrelguard and the slot in a flange of the nozzle.

In the accompanying drawing Figure 1 is a view wherein the presentinvent-ion is exemplified in elevation and partly in section. Fig. 2 isa top view of the barrel guard.

The syringe consists as usual of a glass barrel a with a guard Z), whichhas a lid 0 provided with a bayonet lock, to guide the plunger rod (Z.The glass barrel (1 is provided with a bottom a, the thickness of whichcorresponds approximately with the length of the shank e of the nozzle6. Shank e and bottom a are ground to a tight fit. It will generally besutl icient to press the nozzle tightly into the ground taper bore inthe bottom a, in order to prevent it from slipping from the barrel whilethe syringe is being used. It is, however, desirable to have a morereliable connection between the glass barrel and the nozzle, the guardmantle, which in the constructional form shown rests with a smallcontract-ion only at on the glass bottom a is provided with a specialneck 9, in which at g a radial slot is provided. Correspondingly thenozzle shank c has a pin it projecting at one side, with which itengages in the slot 9' of the neck 9 when the nozzle is inserted intothe glass bottom, and is then turned under it, so that the pin 72,engages under the neck. This will afford a safe lock between the nozzleand the barrel bottom, which is proof againstany unintentional release.

What I claim as my invention and desire to secure by United StatesLetters Patent is:

1. A syringe comprising a glass barrel having a thickened end portionprovided with a tapered bore, a guard surrounding the barrel having aflanged opening at one end, and a nozzle having a tapered shank adaptedto fit in the bore of the barrel and having means for detachablyinterlocking with said guard.

2. A syringe comprising a glass barrel having a thickened end portionprovided with a tapered bore, a guard surrounding the barrel having anopening at one end registering with the bore in the barrel, and closedat the other end by a removable cap, a plunger operable in said barrel,a removable nozzle having a tapered shank adapted to fit in the taperedbore of the barrel, and means for locking the nozzle in the barrel.

3. A syringe comprising a glass barrel having a thickened end portionprovided with a tapered bore, a guard surrounding the barrel, a neckextension formed at one end of the barrel, having an opening and aradial slot, said opening in the neck registering with the bore in thebarrel, a plunger operable in said barrel, a removable nozzle having atapered shank provided with a laterally projecting pin adapted to enterthe slot in the neck extension when the shank is fitted in the bore ofthe barrel, and interlooking with the said neck upon being roi tated.

In witness whereof I have hereunto set my hand 1n presence of twowitnesses.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

